Totally! You can download the Google Cast app onto your Android device & cast the whole screen, which will include Showcase if you open it. The fuller Chromecast help article on this is here.
Slightly different - If you want to cast from a laptop, your showcases are visible at https://app.showcaseworkshop.com, so you could use the Google Cast Chrome extension on that website.
Do bear in mind however that our calculators and .html.zips don't work on the website - they need to be viewed on a tablet to actually function with the calculations etc.